cardiac catheterization to study persons who either have or may have cardiac arrhythmias.

A test that uses cardiac catheterization to study patients who have arrhythmias (abnormal heartbeats). An electrical current stimulates the heart in an effort to provoke an arrhythmia, which is immediately treated with medication. EPS is used primarily to identify the origin of arrhythmias and to test the effectiveness of drugs used to treat them.

or EPS: In this test catheters are introduced into the heart as in cardiac catheterisation (see above). These catheters can record and stimulate the electrical activity of the heart.